01-09 Clinical Assessment of Renal Fx/Urinalysis

Question 1

Remember that patients may present already in chronic renal failure without necessarily knowing it.
—How can you tell if their failure is acute or chronic?

Answer 1

History/Previous blood tests
Kidney size, usually smaller, thin cortex except in:
– Diabetic nephropathy
– amyloidosis
– HIV nephropathy
– Polycystic kidneys
Presence of complications of CKD
– Hyperparathyroidism is first to show up

Question 2

An 67 y/o man suffered a myocardial infarction and underwent cardiac catheterization with placement of three coronary artery stents. Four days later his serum creatinine has increased from 1.1mg/dl to 3.4mg/dl. He also has chest pain again.

Which is the LEAST likely cause of his recurrent chest pain?

1. Coronary artery disease
2. Uremic pericarditis
3. Dressler’s syndrome
4. Pulmonary embolism

Answer 2

2. Uremic pericarditis is LEAST likely cause of his recurrent chest pain.
   —hasn’t been enough time
   —this is a very late manifestation of renal failure

Question 3

An 88 y/o woman weighing 50kg with a serum creatinine of 1.1mg/dl (normal 0.7-1.2mg/dl) has:

1. normal kidney function
2. stage 3 CKD
3. Stage 4 CKD
4. needs immediate dialysis

Answer 3

3. Stage 4 CKD

—point, have to interpret CrCl w/ pts age, sex and muscles mass in mind!!!

Question 4

Equation for Creatinine Clearance?

Answer 4

Urine Cr (mg/dl) x 24hr Urine Vol (ml)
------------------------------------------
Serum Cr (mg/dl) x	1440 min

—Use National Kidney Assoc app to get eGFR via
—Cockroft-Gault Equation
—MDRD

Question 5

Staging of CKD is based on

Answer 5

GFR and ?albuminuria

Question 6

Urine production
—oliguric lower limit
—polyuria upper limit

Answer 6

< 500cc/day - oliguria

> 3000cc/day - polyuria

Question 7

cloudy urine

Answer 7

pyuria

Question 8

foamy urine

Answer 8

means high level proteinuria

Question 9

Coffee/ Coca cola (red/brown) urine

Answer 9

GN

Question 10

Red/brown urine

Answer 10

macroscopic hematuria

Question 11

Particles in urine

Answer 11

entero-vesical fistula

Question 12

black urine

Answer 12

melanuria (melanoma)

Question 13

white urine

Answer 13

chyluria (filariosis, tuberculosis, cancer)

Question 14

orange urine

Answer 14

Rifampicin

Question 15

green urine

Answer 15

propofol vs. pseudomonas

Question 16

red urine

Answer 16

hematuria vs. Beeturia

Question 17

blue urine

Answer 17

methylene bleu

Question 18

Purple urine bag

Answer 18

—occurs in people w/ catheters and UTI
—Bacteria produce indoxyl phosphatase: indoxyl sulfate in the urine into the red and blue colored compounds indirubin and indigo.
—most commonly implicated bacteria are Providencia stuartii, Providencia rettgeri, Klebsiella pneumoniae, Proteus mirabilis, Escherichia coli, Morganella morganii, and Pseudomonas aeruginosa.[2]

Question 19

Leucoesterase (on dipstick)

Answer 19

detects esterase, an enzyme released by white blood cells

—good predictor of UTI when combined w/ nitrite

Question 20

Dipstick: Glucosuria without diabetes

Answer 20

Fanconi (reabsorption problem w/ many substances in PT)

Question 21

Dipstick: Weak protein signal despite significant quantity of protein measured in lab:?

Answer 21

Bence-Jones Proteins/Paraproteins

—b/c strip only measures [albumin]

Question 22

Dipstick: Heme positive in little stains

Answer 22

microscopic hematuria

Question 23

Dipstick: Heme positive homogenously

Answer 23

hemoglobinuria vs. myoglobinuria

Question 24

nephritic syndrome

Answer 24

HTN, hematuria, edema, flanc pain, increased creatinine
—GN: Mesangial and subendothelial deposits in contact with bloodstream, producing inflammation, proliferation and hematuria

Question 25

nephrotic syndrome

Answer 25

Edema, foamy urine (proteinuria), hyperlipidemia, low BP, often normal creatinine —Lesion of epithelial cells and glomerular basement membrane, not in contact with bloodstream, characterized by heavy proteinuria

Question 26

good estimation of 24hr urine protein

Answer 26

spot urine protein/creatinine ratio

Question 27

FENa —Equation —Interpretation

Answer 27

(U/P) Na ------------ x 100 (U/P) Cr Interpretation —Normal and prerenal 2% **Take w/ big grain of salt

Question 28

Urine findings of tubulo-interstitial dz vs. Glomerular

Answer 28

TUBULO-INTERSTITIAL —Proteinuria < 3gm/day —Isostenuria (Urine SG = prot-free plasma SG) —Glucosuria ``` GLOMERULAR —Proteinuria > 3gm/day —Acanthocytes —RBC casts —Lipid casts ```

Question 29

Tamm-Horsfall Glycoprotein

Answer 29

~urinary mucous replacement —in solution —prevents UTIs by binding

Question 30

Clear hyaline casts

Answer 30

nl finding

Question 31

significance of RBC casts

Answer 31

hematuria is of renal origin

Question 32

See acanthocytes and RBCs casts on light microscopy. Dx?

Answer 32

GN

Question 33

See granular casts. DX?

Answer 33

Granular cast: ATN?

Question 34

Oval fat bodies, fatty casts, cholesterol crystals. Dx?

Answer 34

nephrotic syndrome

Question 35

Cystine crystals

Answer 35

cystinuria

Question 36

CaOx crystals

Answer 36

normal or oxalosis, hyperoxaluria, ethylene glycol ingestion (antifreeze)

Question 37

Maltese cross

Answer 37

fat crystals

Question 38

brick dust crystals

Answer 38

urate | —no pathology

Question 39

60 year old male with low back pain since 4 months found to have creatinine 2.4mg/dl. His urine dipstick shows trace protein and trace blood. His protein/creatinine ratio is 2.4. What is his most likely diagnosis? 1. Membranous nephropathy 2. Myeloma kidney 3. Rhabdomyolysis 4. Diabetic nephropathy

Answer 39

2. myeloma kidney?

Question 40

See small kidney (in adult) on renal U/S?

Answer 40

CKD

Question 41

malar rash

Answer 41

SLE | —butterfly distribution

Question 42

missing patella

Answer 42

nail-patella syndrome | —has renal complications

Question 43

Sinus disease, bloody nasal discharge, saddle nose

Answer 43

Wegner's —vs. Goodpasture's —vs. anti-GBM

Question 44

Post-valsalva periorbital purpura

Answer 44

amyloidosis

Question 45

deafness and hematuria

Answer 45

Alport's

Question 46

Ash leaf spots

Answer 46

tuberous sclerosis

Question 47

S/Sx of Uremia

Answer 47

``` SYMPTOMS Nausea, vomiting: like a nasty hangover Tiredness: low epo Weakness: ?anemia, high [K+] Dyspnea Edema Pruritus Encephalopathy ``` ``` SIGNS Foetor uremicus (smell like piss) Hyperpigmentation Uremic Frost Cachexia Pruritus, scratch marks Pallor of anemia Asterixes, confusion, coma Friction rub/distant cor sounds (uremic pericarditis) Pulmonary edema Muscle weakness from hyperkalemia Cardiac arrythmia from hyperkalemia ```

Question 48

High total urine protein but negative dipstick?

Answer 48

myeloma | —paraproteins don't show up